The introduction of the idle fee is a great addition that will help promoting certain behaviour. However, it is not convenient forcing people to get up in the middle of the night to move their car because it is done charging. Therefore I suggest introducing the possibility of only enforcing the fee at certain times i.e. a schedule.
Thanks, happy you like it! :)
We're adding scheduled price-changes as we speak. It will work as a schedule, so you can plan what price-groups to be applied when, and thus only apply price groups with fees in the timeframe that fits your need :-)